Answer:
B
B
A
C
D
Explanation:
I think dont take my word for though
Answer:

Explanation:
The work function of the sodium= 495.0 kJ/mol
It means that
1 mole of electrons can be removed by applying of 495.0 kJ of energy.
Also,
1 mole =
So,
electrons can be removed by applying of 495.0 kJ of energy.
1 electron can be removed by applying of
of energy.
Energy required =
Also,
1 kJ = 1000 J
So,
Energy required =
Also,
Where,
h is Plank's constant having value
c is the speed of light having value
So,
Also,
1 m = 10⁻⁹ nm
So,

Molar mass Ra(OH)2 = 260 g/mol
<span>Moles = 987 g / 260 = 3.80 moles</span>
Answer: The capillary rise(h) in the glass tube is = 0.009m
Explanation:
Using the equation
h = 2Tcosθ/rpg
Given
Contact angle, θ = Zero
h = height of the glass tube=?
T = surface tension = 
r = radius of the tube = 0.1mm =0.0001m
p= density of ethanol = 
g= 
h = 
h= 0.09m
Therefore the capillary rise in the tube is 0.09m
Answer:
a lithium atom (Z=3, A=7 AMU) contains three protons (found from Z), three electrons (as the number of protons is equal to the number of electrons in an atom), and four neutrons (7 – 3 = 4).
Explanation: